An ionic self-assembly approach towards sandwich-like graphene/SnO2/graphene nanosheets for enhanced lithium storage

Abstract

Two-dimensional graphene/SnO₂/graphene (G/SnO₂/G) hybrids with SnO₂ nanoparticles sandwiched in graphene sheets have been constructed by a facile ionic self-assembly process. The resulting G/SnO₂/G hybrids possessed flexible and ultrathin graphene shells that effectively enwrapped the SnO₂ nanoparticles. When the hybrids were used as the anode materials in lithium-ion batteries (LIBs), their unique core–shell architecture provided double protection against the aggregation and volume changes of SnO₂ nanoparticles, and ensured favorable transport kinetics for charge carriers. As a result, the hybrids exhibited a superior cycling stability (600 mA h g⁻¹ over 60 cycles) and excellent rate capability (120 mA h g⁻¹ at 5.0 A g⁻¹).